TUESDAY, Jan. 28, 2014 (HealthDay News) -- A simple breath test might reveal if a person has early-stage lung cancer, according to a new study.

Researchers tested the exhaled breath of people with suspicious lung lesions that were detected on CT scans. The breath was tested for levels of four cancer-specific substances, called "carbonyls."

The breath samples were analyzed using a special device developed at the University of Louisville.

Having elevated levels of three of the four carbonyls was predictive of lung cancer in 95 percent of patients, while having normal levels of these substances was predictive of a noncancerous growth in 80 percent of patients, the researchers found.

Elevated carbonyl levels returned to normal after lung cancer patients had surgery to remove the cancer, according to the study, which was to be presented Tuesday at the Society of Thoracic Surgeons annual meeting in Orlando, Fla.

"Instead of sending patients for invasive biopsy procedures when a suspicious lung mass is identified, our study suggests that exhaled breath could identify which patients" may be referred for immediate surgery, study author Dr. Michael Bousamra, of the University of Louisville, said in a society news release.

This approach offers something new, he said, including "the simplicity of sample collection and ease for the patient."

The data and conclusions of research presented at medical meetings should be viewed as preliminary until published in a peer-reviewed journal.